Rear turn signal and hazard light don't flash (left side only)

Generally speaking, symptoms of a bad or failing turn signal bulb are usually the culprit...in your case, either it's the front left or rear bulb. Varies for different vehicle makes...common signs include:

1. turn signal light staying on solid
2. or blinking very fast
3. or either sides of the bulbs stop blinking altogether.

To test this, make sure you reconnect everything you disconnected.
Turn the left signal light on; go to the front of the vehicle, is the turn signal bulb illuminated? If it lights up, even though it is not blinking obviously the bulb is okay. If it doesn't, replace it- problem solved. You'll do the same procedure for the rear turn signal Is that lit up? If not replace the bulb and the problem is solved.
Another common failure is when the turn signal blinks really fast, same procedure as mentioned above.
If both bulbs for the left side and right side illuminate but don't blink, the problem is in the steering column turn signal switch.
If the left or right side blinkers don't work properly at all...then check the integrated hazard warning/turn signal flasher relay- that may be defective; again, that's usually the case if both sides of the signal light don't work.
If you are blowing any fuses related to the flasher system, you have an electrical overload in the turn signal circuitry.

sounds like one of light bulbs was malfunctioning and caused the flasher unit to blink rapidly and iy burned out. Replace front and rear turn lite bulbs and see if flasher flashes. if not check fuse and replace fuse. If fuse okay replace flasher unit. Good luck

You will be needing a good electric meter.
With the key on and the turn signal activated, test the leads inside the light socket and see if electricity is getting to the bulb.
When you mentioned it flashes really fast, that says one of the bulbs is not working.
Although it could be burned out, it could also not be making contact, or the ground wire could be bad.
Since the early '80's, cars and trucks have had separate ground wires to each and every bulb and electrical component, and a bad ground will cause this problem also.
Remember, a bulb can look good and still be no good.
God bless your efforts.

Sometimes the housing the bulb is in has gone bad try cleaning out the prongs where the bulb goes in it that does not work replace the fixture the bulb goes in had the some thing happen to my trailblazer hope this helps

Gday mate, we had a problem with another late model vehicle similar to that, the bulb that was put into the reverse light was not exact brand product ( ohmage was slightly wrong ) and fowled up computer, correct bulb in place and disconnect battery to reset K A M ( keep alive memory) problem solved, BEWARE, some vehicles cannot have KAM reset except for dealer computer tethered reboot , just try putting the factory correct bulb(s) in and see how it goes, geoff. hope this helped.

First, is it doing it on BOTH isdes or just on one side? Example: turn signnals flash OK when turning left, but only come on and stay on when turning right. If it is doing this, then you most likely have either a blown bulb or a bad bulb socket on the side that is not flashing. You need to check both the FRONT and REAR bulbs to make sure they are all functioning properly.
If it is doing it on BOTH sides, then you either have a bad flasher, or at least 2 bulbs burned out (one or more on each side).

Are you sure you replaced the correct flasher? The flasher for the HAZZARD lights is plugged into the convinience center under the left side of the dash. If this is the flasher you replaced, it is the wrong one.
The turn signal flasher is mounted to the driver's knee bolster bar near the steering column. It is held to the bar with a clip. (see diagram)

try running a new ground to the left socket,

Usually a fast flashing signal is because one of the bulbs is burned out or shorted out. If the signal and brakes use the same light which many cars do then check the wiring to it and replace bulb. If burns out again then it has a short between the signal switch and the actual light or the brake wiring to it is shorted.

Check the front lights. Usually if i flashes fast it indicate a bulb is out on that side.

What may have happened is either the headlights wiring or the parking lights wiring somewhere along the wiring fused to the left turn signals wiring. Depending on if the turn signals go on when you put the parking lights on or the headlights on.

If the signals come on when you turn on the headlights than you only need to locate the light green wire that comes off the left turn signal harness.

Next follow that wire the entire way back to the firewall looking for another wire fused to that wire as you go.

If there are no signs of this you need to continue looking on the other side of the firewall all the way back to the turn signal and hazard flasher unit which is a black box that connects to a black harness located next to a grey harness behind the knee bolster.

But if the signals come on when you turn on the parking lights than you will also need to check the wiring from the rear left signal and follow that light green wire all the way back to the turn signal and hazard flasher unit.

This should fix your problem, but if not than your problem may lay within the the wiring between the turn signal/hazard switches and the turn signal and hazard flasher unit.

Also you may have a burnt circuit in the junction block. This block is where the light green from the rear left signal and front left signal meet. Don't have a description but if you cannot find it let me know and I will go out to the yard and look myself and let you know.